Transcript A&P I Exam 1 Review Slides Spring 2014 Lectures 1-4 Chapters 1 and 2

A&P I Exam 1 Review Slides
Spring 2014
Lectures 1-4
Chapters 1 and 2
1
Overview of Anatomy and Physiology
Anatomy – study of structure
- Gross anatomy – macroscopic (types?)
- Cytology (microanatomy) – cells
- Histology (microanatomy) – tissues
Physiology – study of function
- Specialized, e.g., neuro-, cellular-, patho-
- Comparative physiology
Structure is always related to function;
if structure changes, function changes
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General Function of Organ Systems
A&P I
A&P II
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Serous Membranes
Thin layer of tissue lining a body cavity that secretes serous fluid
Visceral layer – covers an organ
Parietal layer – lines a cavity or body wall
Thoracic Membranes
•Visceral pleura
•Parietal pleura
•Visceral pericardium
•Parietal pericardium
Abdominopelvic Membranes
•Visceral peritoneum
•Parietal peritoneum
Serous fluid – thin, watery, slippery fluid typically
separating serous membranes
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Serous Membranes
What is the mediastinum?
Be able to label ALL parts of this diagram; (What system is each organ a part of?)
** See the gserianne.com Web site for downloadable blanks to label
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Serous Membranes
Be able to label ALL parts of this diagram
(What system is each organ a part of?)
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Homeostasis
A CRITICAL (and very testable) concept in physiology
Body’s maintenance of a stable internal environment
**Absence of homeostasis = DISEASE
Homeostatic Mechanisms – monitor aspects of the
internal environment and corrects any changes
Components of homeostasis:
•Receptors - provide information about environment
•Control center - tells what a particular value should be
•Effectors - causes responses to change internal
environment
Negative feedback – deviation from set point progressively lessens
Positive feedback – deviation from set point gets progressively greater
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Homeostasis
• Remember that homeostasis does NOT mean
constant!
– Continual variations occur in body systems
– Gives rise to ‘normal ranges’ (See Appendix B)
• Examples of negative feedback
– Temperature regulation, blood pressure, blood
glucose levels
• Examples of positive feedback
– Blood clotting, milk production, uterine contraction
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Levels of Organization
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Important Definitions of Organizational Terms
• Cell – The basic unit of biological structure and
function (what is a ‘basic unit’ of something?)
• Tissues – A group of cells working together to
perform one or more specific functions
• Organs – Two or more tissues working in
combination to perform several functions
• Organ System – Interaction of organs
functioning closely together
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Atomic Number
Atomic Number
• number of protons in the nucleus of one atom
• each element has a unique atomic number
• equals the number of electrons in the atom in an
electrically neutral, i.e., uncharged, atom
Written as a subscript to the left of the element's symbol.
Example: 11Na
In a neutral atom, # protons = # electrons.
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Atomic Mass Number (Weight)
• Atomic Mass Number
– the number of protons plus the number of
neutrons in one atom
– electrons contribute negligibly to the weight
of the atom, so for our purposes we can
consider the atomic weight = atomic mass
number
Written as a superscript to the left of an
element’s symbol.
Example:
23
Na
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Determining Atomic Number & Atomic
Mass Number
What is the atomic number?
What is the atomic mass number (weight)
12 C
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What is the number of protons?
What is the number of electrons?
What is the number of neutrons?
14 C
6
What about this form of Carbon???
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Periodic Table of the Elements
Groups
The
“magic
numbers”
From: Trefil, Hazen, The Sciences, 4th ed., Wiley Press, 2004
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Ions
Ion
• an atom that has gained or lost one or more electron(s)
• an electrically charged ‘atom’
• atoms form ions to become stable
Cation (CA+ION)
• a positively charged ion
• formed when an atom loses one
or more electron(s) (oxidation)
Anion
• a negatively charged ion
• formed when an atom gains one or
more electron(s) (reduction)
To remember oxidation/reduction, think:
“OIL RIG”
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Isotopes
Isotopes
• atoms with the same atomic numbers but
with different atomic weights
• atoms with the same number of protons and
electrons but a different number of neutrons
• oxygen (atomic number 8) has the
following isotopes (16O, 17O, 18O)
• unstable isotopes (radioisotopes or
radionuclides) are radioactive; they emit
subatomic particles.
• **Not all isotopes are radioactive
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Most common elements in the human body (by weight)
96%
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Types of Chemical Bonds
• There are three major types of chemical bonds
to know…
– Ionic (electrovalent) bonds – attraction between
oppositely charged ions
– Covalent bonds – sharing of electrons
– Hydrogen bonds – weak, electrostatic interaction
between atoms
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Chemical Bond Summary
TYPE OF BOND
DEFINITION
DESCRIPTION
EXAMPLE
IONIC
when atoms lose or gain
electrons becoming
ions, and then
oppositely charged ions
are attracted to one
another
bond is broken by water
salts, NaCl
COVALENT
when 1 or more pair(s) of
electrons is/are shared
by atoms
(single, double, triple)
strong bond
the bonds holding a
molecule of H20
together, CO2
HYDROGEN
when a (slightly positive)
hydrogen atom that is
already covalently
bonded to a molecule is
attracted to a slightly
negative atom.
Very weak bond; in
molecules whose
purpose is to easily
break and then come
back together
reactions between water
molecules (i.e. ice to
water to gas);
DNA chains
(typically with O, N)
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Types of Chemical Reactions
Synthesis Reaction (also called condensation or dehydration
synthesis reactions when water is released)
– chemical bonds are formed (requires energy)
A + B  AB
Decomposition Reaction (also called hydrolysis when water
is used for decomposition)
– chemical bonds are broken (liberates energy)
AB  A + B
Exchange Reaction – chemical bonds are broken and formed
AB + CD  AD + CB
Reversible Reaction – the products can change back to the
reactants
A + B n AB
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Summary of Reaction Types
SYNTHESIS REACTIONS
DECOMPOSITION REACTIONS
GENERAL DESCRIPTION
Synthesis involves the building of a
large molecule (polymer) from
smaller building blocks
(monomer).
Decomposition involves the breakdown
of a polymer into individual
monomers.
DESCRIPTIVE TERMS
building
constructive
anabolic
breakdown
digestive
decomposition
catabolic
BOND FORMATION OR
BREAKING?
Bonds are formed.
Bonds are broken.
IS ENERGY REQUIRED
OR RELEASED?
NAME THAT TERM.
Energy is required to form the bond.
(Endergonic)
Energy is released when the bond is
broken.
(Exergonic)
HOW IS WATER
INVOLVED?
NAME THAT TERM.
Water is released when he bond is
formed.
Dehydration synthesis
Water is required to break the bond.
Hydrolysis
EXAMPLE
Building a protein from individual
amino acids;
Building a triglyceride from glycerol
and 3 fatty acids, etc
Breaking a protein into individual
amino acids;
Breaking starch down into
monosaccharides, etc.
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Equilibrium
At equilibrium, the ratio of products to reactants stays constant
Note that equilibrium does NOT necessarily mean that the
concentrations of reactants and products are equal!
Figure from: Alberts et al., Essential Cell Biology, Garland Publishing, 1998
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Acids, Bases, and Salts
Electrolytes – soluble inorganic substances that release ions in
water (aqueous) and will conduct an electrical current
NaCl  Na+ + Cl-
Acids – substances that release hydrogen ions (protons) in water
HCl  H+ + Cl-
Bases – substances that release OH- (or other negative) ions in
water that can combine with, and remove, H+ from solution
NaOH  Na+ + OH-
Salts – electrolytes formed by the reaction between an acid
and a base (anions/cations EXCEPT H+ or OH-)
HCl + NaOH  H2O + NaCl
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pH (H+ concentration)
*Notice: [H+], pH, [OH-]
*Notice: [H+], pH, [OH-]
pH scale - indicates the concentration of FREE hydrogen ions in
solution (think: “power of Hydrogen”)
*pH of human blood plasma = 7.35 – 7.45 (AVG = 7.4)
- Acidosis  7.35
- Alkalosis  7.45
- pH  7.8 causes uncontrolled skeletal muscle contractions
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Solutions
• Solutions contain
– Dissolved substances: solutes
– The substance doing the
dissolving: solvent, e.g. water
• Concentration of a solution is
the amount of solute in a
particular volume of solvent
– Example: Grams per liter (g/L)
– Example: Milligrams per liter
(mg/L)
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Moles and Molarity
• A ‘mole’ is the atomic/molecular weight of an
element expressed in grams
– Example: 1 mole of 23Na = 23 grams (g)
– Example: 1 mole of 1H = 1 g
– Example: 1 mole of H2O = 18 g
• Molarity (M) is the number of moles of a solute
dissolved in 1 Liter (L) of solvent, i.e., moles/L
– Example: 1 mole Na in 1 L H2O = 1M Na solution
– Example: 2 moles Na in 2 L H2O = ?M Na solution
– Example: 1 millmole Na in 1 L H2O = ?M Na solution
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Organic Molecule
Carbohydrates (sugars)
Lipids (Fats)
Proteins
Nucleic Acids
Composed of what
atoms?
C, H, O
C, H, O
C, H, O, N, S
C, H, O, N, P
Building Blocks
(monomers)
Monosaccharides, e.g.
hexoses (6-carbon)
Triglycerides: glycerol
and 3 fatty acids
Phospholipid: glycerol,
2 FA, phosphate
Steroid: cholesterol
amino acids
nucleotides: pentose
sugar, phosphate,
nitrogen base
Specific types &
functions of
monomers
Mono-; glucose, fructose,
galactose
N/A
20 different amino
acids; each differs
from the others
because of its
unique R group
N/A
TG: energy
Phospholipid: cell
membrane
component
Steroid: cell membrane
component and
chemical
messenger (i.e.
cholesterol)
proteins (>100 amino
acids);
Many functions:
ENZYMES,
antibodies, structure,
transport, chemical
messengers,
storage
DNA: deoxy-ribonucleic
acid; genetic
material; RNA:
ribonucleic acid; aids
DNA in protein
synthesis.
Saturated (only single
bonds between C’s
in FA chain) vs.
Unsaturated (at
least 1 double
bond in FA chain)
Amino acids are joined
together by peptide
bonds
DNA controls cellular
activity by
instructing our
cells what proteins
to make (i.e.
Enzymes through
protein synthesis).
Glucose = body’s energy
source
Specific types and
functions of
polymers
Other
Information
Disaccharides:
sucrose, lactose, maltose;
energy
_____________
Polysaccharides
Starch (plant);
Glycogen (animal); energy
storage.
Dipeptide = two aa
Tripeptide = three aa
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Enzymes and Metabolic Reactions
Biological catalysts, i.e., speed up reactions without being changed in the process.
• control rates of metabolic reactions
• lower activation energy needed to start reactions
• two important factors controlling enzyme activity: temperature and pH
• not consumed in
chemical reactions
• substrate specific
• shape of active site
determines which
substrate(s) the
enzyme can act on
Figure From: Marieb & Hoehn, Human Anatomy & Physiology, 9th ed., Pearson
Many times the name of an enzyme ends with suffix ‘ase’
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Cofactors and Coenzymes
Cofactors
• make some enzymes
active
• ions or coenzymes
Coenzymes
• complex organic molecules
that act as cofactors (so
coenzymes ARE cofactors)
• vitamins
• NAD+
Vitamins are essential organic substances that human
cells cannot synthesize, i.e., they must come from the diet
- required in very small amounts
- examples - B vitamins: Thiamine (B1), niacin
The protein parts of enzymes that need a nonprotein part
(coenzymes, cofactors) to work are called apoenzymes
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ATP – An Activated Carrier Molecule
• each ATP molecule has three parts:
• an adenine molecule
These two components
together are called a ?
• a ribose molecule
• three phosphate molecules in a chain
• ATP carries its energy in the form or P
(phosphate)
• ATP is valuable because it is a readily
interchangeable form of energy for
cellular reactions (“common currency)
Figure From: Marieb & Hoehn, Human Anatomy & Physiology, 9th ed., Pearson
High-energy bonds
Be able to
explain or
diagram this
Figure from: Hole’s Human
A&P, 12th edition, 2010
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